The steps of a normal escalator are fastened to two transport chains and together with the latter form an endless circulating step band that runs over a pair of transport chain wheels at both ends of the escalator, one transport chain wheel pair belonging to a drive station and driving and reversing the step band and the other chain wheel pair being part of a step band reversing station. The individual steps of the step band are each equipped with two front and two back guide rollers on which the steps are guided in a positionally dependent defined position by guide rails and reversing cams that are mainly fastened to the supporting construction of the escalator.
The steps of the escalator run along a predetermined path that is defined at the sides by stationary skirt panels. A passenger that is present on the step tread surface of a step stands facing the step riser surface of the preceding step. In the exit area, the following step slides along the step riser surface of the preceding step and then under a comb plate, so that the step tread surfaces of the preceding and following step come onto the same level and disappear under the comb plate. The comb plate has a step comb that has comb teeth. The step tread surfaces of the steps have ribs that pass between the comb teeth to remove objects that could be present in the ribs before the steps disappear under the comb plate and return to the other end of the escalator. There is, however, nevertheless a hazardous or dangerous gap between the ribs of a step and the step comb.
To compensate for tolerances, a gap must remain between the ribs of a step and the step comb. Otherwise, considerable friction would be generated that would cause inadmissible heating and would increase escalator driving power and wear. Thus, a gap or air gap must remain between the ribs of a step and the step comb.
Such a gap or air gap is a safety risk. Because of the play that is present, the gap width can become a large area so that insertion of a shoe edge, scarf, high heel, skirt hem, or hand, especially by children, becomes possible. In consequence, the danger of contusions and other injuries to passengers is not ruled out.
Injury to persons in the area of the comb plate caused by the relative movement between the moving steps and the stationary comb plate is a main problem of conventional escalators. In addition, if an object that is present on the moving step comes into contact with the step comb, the object can be pulled by friction and relative movement into the gap, especially at that comb plate where passengers leave the escalator. This is the upper comb plate when traveling up, and when traveling down, the lower comb plate.
Patent JP2000000529 discloses brushes that are arranged on a comb plate to clean the step tread surface of the step. In this device, the brushes are present at a certain spaced distance behind the step comb, so that objects can become jammed in the underlying gap. Moreover, the brushes are in contact with the step tread surface of the step, which can damage the step tread surface and cause noises. It has also proved disadvantageous that the brushes have a very short life due to the constant friction with the step tread surface. The forces that are exerted by the steps damage the structure of the brushes and cause their shortening. They have also been proven to have insufficient form, load, and contact stability.
The objective of the invention is therefore to create an escalator or moving walk that does not have disadvantages of the prior art and that essentially increases the operating safety and significantly lengthens life of the step tread-comb plate system while being simple to manufacture.